<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        * {
            margin: 0;
            padding: 0;
        }

        .input-box {
            margin: 10px;
            display: flex;
            align-items: center;
        }

        .input-box input {
            flex: 1;
            height: 40px;
            border: 1px solid #ccc;
            outline: none;
            padding-left: 20px;
            border-radius: 5px;
        }

        .input-box span {
            text-align: center;
            color: lightseagreen;
            width: 60px;
        }

        .list {
            margin: 10px;
        }

        .list .task {
            margin: 20px 0;
            display: flex;
            justify-content: space-between;
            padding: 15px;
            background-color: red;
            color: white;
        }

        .list .task.finished {
            background-color: lightseagreen;
        }

        .empty {
            text-align: center;
            margin: 50px 0;
            color: red;
        }

        .titel {
            display: flex;
            padding: 25px;
            justify-content: space-around;
        }

        .titel span {
            display: inline-block;
            padding: 15px;
            color: white;
            background-color: lightseagreen;
        }

        .titel span.one {
            background-color: red;
        }
    </style>
</head>

<body>
    <div id="app">
        <div class="input-box">
            <input type="text" placeholder="输入任务名称" v-model="inputText">
            <span @click="add">新增</span>
        </div>
        <div class="titel">
            <span>全部任务({{tasklist.length}})</span>
            <span>已完成({{titelist}})</span>
            <span class="one">未完成({{onelist}})</span>
        </div>
        <div class="list">
            <div :class="{ task: true, finished: item.status }" v-for="(item,index) in tasklist" :key="index">
                <input type="checkbox" @click="changeStatus(item)">
                <div class="name">{{item.name}}</div>
                <span class="btn" @click="removetext(index)">删除</span>
            </div>
            <div class="empty" v-show="tasklist.length == 0">任务列表空空如也!</div>
        </div>
    </div>

</body>

</html>
<script src="./vue-2.5.21.js"></script>
<script>
    var v = new Vue({
        el: '#app',
        data: {
            inputText: '',
            tasklist: []
        },
        methods: {
            add() {
                if (this.inputText) {
                    var obj = { id: this.tasklist.length + 1, name: this.inputText, status: false };
                    this.tasklist.push(obj);
                    this.inputText = '';
                }
            },
            changeStatus(item) {
                item.status = !item.status;
            },
            removetext(index) {
                if (index != -1) {
                    this.tasklist.splice(index, 1)
                }
            },
        },
        computed: {
            titelist() {
                return this.tasklist.filter((item) => { return item.status }).length;
            },
            onelist() {
                return this.tasklist.length - this.titelist;
            }
        }
    })
</script>